1. Field of the Invention
The present invention relates to a sheet post-processing apparatus that performs post-processing (stapling, booklet processing) on sheets on which an image is formed by an image forming apparatus such as an electrophotographic-type of copy machine, printer, or the like.
2. Related Art
Generally, a sheet post-processing apparatus that is attached to an image forming apparatus such as an electrophotographic-type of copy machine, printer, or the like has functions of collecting sheets on which an image is formed by way of an image forming apparatus so as to bind a stack of sheets thus collected at one place or at a plurality of places (staple processing) and binding the sheets on which images are formed in a magazine-like style (booklet processing). In addition, in order to improve the productivity of the image forming apparatus, the sheet post-processing apparatus has a holding path that allows the sheet delivered from the image forming apparatus to be held singularly or held by being stacked in plurality during stapling.
With the conventional technology, sheet post-processing apparatuses equipped with functions of stapling or booklet processing are configured to deliver the sheets on which images are formed by way of the image forming apparatus to a post-processing tray through a first delivery path and collect the sheets in the post-processing tray. A stack of sheets thus collected in the post-processing tray is bound at one place or a plurality of places by a stapler (stapling). Furthermore, the conventional sheet post-processing apparatus includes a second delivery path (delivery holding path) that branches off from the first delivery path. Then, one or a plurality of sheets is also held in the second delivery path while stapling. Moreover, the sheet post-processing apparatus includes a third delivery path that branches off from the first delivery path. Then, the sheet post-processing apparatus delivers via the third delivery path the sheets on which images are formed to an apparatus that performs booklet processing.
In the sheet post-processing apparatus, switching to the first delivery path, the delivery holding path, or the third delivery path is performed by a plurality of switching means (flappers) that is provided in a dedicated space at a delivering entrance side of the sheet post-processing apparatus.
However, in the conventional technology, a switching means that connects the third delivery path with the apparatus that performs booklet processing is provided in a dedicated space at a delivering entrance side of the sheet. Therefore, the horizontal width of the sheet post-processing apparatus increases. On the other hand, attempting to suppress the increase in the horizontal width of the sheet post-processing apparatus leads to another problem in that it is not possible to deliver cardboard sufficiently since the radius of curvature of the second delivery path will be small.
Furthermore, in the conventional technology, the first delivery path, the delivery holding path, and the third delivery path are formed independently. As a result, there is also a problem in that the cost of forming the first delivery path, the delivery holding path, and the third delivery path increases and the space for forming the same becomes large.